Add ARIA labels to all icon-only buttons for screen reader accessibility

[georgi]

Problem

Many IconButton components lack aria-label attributes, making them inaccessible to screen readers. Users who rely on assistive technology cannot understand what these buttons do.

What to do

1. Search for all <IconButton components in web/src/ that don't have an aria-label prop
2. Add a descriptive aria-label to each one (e.g. aria-label="Close", aria-label="Delete item", aria-label="Toggle settings")
3. Also check for <button> elements that only contain an icon (no text) — these need labels too
4. Ensure interactive elements that look like buttons use <button> or have role="button" + tabIndex={0} + keyboard handlers

Guidelines

• Labels should be concise and action-oriented
• Use the button's actual function, not the icon name (e.g. "Close dialog" not "X icon")
• Don't add labels to buttons that already have visible text